To work off a large pizza that you ate on Friday night, Saturday morning you climb a 120 m hill.
a) Assuming a reasonable value for your mass, find your increase in gravitational potential energy.
b) Determine where does the energy come from?
c) The human body is typically 20 percent efficient, find how much energy was converted into thermal energy?
d) Determine how much chemical energy is expended by you during the climb? Given that the burning of a single slice of pizza is about 1.0 MJ (250 food calories) of energy, do you think the one climb up the hill was enough?